The symposium, "Functions and Actions of Retinoids and Carotenoids: Building on the Vision of James Allen Olson," to be held at Iowa State University, will focus on the physiological roles (functions) and pharmacological roles (actions) of retinoids and carotenoids. Professor James Allen Olson, who provided a unique and outstanding example of the recent developments in the retinoid and carotenoid fields, died on September 22, 2000. The symposium, while paying tribute to Dr. Olson's contributions, will bring together scientists from these fields to share recent findings and to promote interdisciplinary communications. Specific presentations have been identified to address bioavailability of these compounds as dietary components and interrelationships among dietary components; mechanisms underlying the relationships between diet and optimal health (including approaches from both epidemiological and laboratory research); cellular and molecular mechanisms of retinoid and carotenoid action, with particular emphasis on regulation of gene expression (including cancer prevention and treatment); and public health recommendations for dietary intakes and for interventions to improve nutritional status and to prevent and ameliorate disease. This symposium is intended to provide updated scientific information across a variety of fields constituting human health issues. It is intended to foster interactive collaborations among participants and speakers, bring attention to different fields of study, especially for graduate students and postdoctoral fellows, and to bring new ideas, methods and materials to the attention of other workers.